What in the world?

[LagunaGlide]

So I was watching the tank, and my sailfin did this little shakey swim move, and this thing came off. At first I thought it was a big chunk of food until closer inspection. So I netted it out and took a few pics. Anyone know what the heck this is?

 

[SAPPER]

Is it moving? Maybe put it in a bit more water to make it more visible.

 

[Maritimer]

Almost looks like grains of sand trapped in something ... what, though, I cannot begin to say.

~Bruce

 

[jasonrusso]

Looks like a cerith. Sometimes mine have sand stuck to them.

 

[LagunaGlide]

It does not appear to be capable of it's own movement. It literally just floated around in the tank once it came off. I had it in more water, but was harder to get a good pic. It's gone now. Several of the other fish tried to eat it, but spit it back out, so I assume it's not tasty. I would assume that it is sand in it though. Maybe it's a scab?